elxxiv Proceedings of the Asiatic Society of Bengal. [N.S., XV, 
To put the matter bluntly—an apparent ortho-gneiss with 
its contemporaneous veins may quite as well be an in- 
eure metamorphosed sediment with pegmatities formed 
t by ‘selective solution’ as it may be the extreme, 
foliated or otherwise modified, se prcomp anlar? of a canta 
gabbroid or hybrid abyssal injectio 
Perhaps, I may be now sanggiene . express my own views 
‘Dileite eile’. on these points ; for, without formulat- 
ing, as far 
to the origin and reliationahips of the various members of the 
Archaean complex, it is impossible to deal satisfactorily with 
Laeagptag of ore genesis in the Archaean. Most of my field- 
k in India has been devoted to the study of ore-deposits 
located in Archaean formations or to the geological oe of 
areas in which Archaean formations predominate. In particu- 
lar a phe has lain in the Central Provinces and in Singh- 
bhum, but I have also been fortunate in being able to visit at 
one time or another Ajmer-Merwara, Central India, Hazari- 
bagh, Orissa, Sikkim, Ganjam, Vizagapatam, Bellary, the 
Sandur and Nilgiri Hills, Mysore State, Ratnagiri, and Portu- 
ese India, saad have thus been enabled to examine typical 
exposures of all the formations of Dharwarian aspect, viz. the 
arwars, Champaners, pi Ghat series, the Aravallis, and 
i Dalings, to study the relationships to these formations to 
e Archaean —. bere granites, and also to make the 
cquaintance of the rn Ghats type of Archaean rocks, 
aes terised sectaly “ay this khondalite and charnockite 
‘Baal on this ss oc wert I feel convinced that we saat 
the lace, accept a eral 
oontonspardnelty for the Pviectinis of 
Dharwaria ie . This view cannot, 
ourse, be supported on palzonto- 
logical grounds, as no satisfactory evidence of the existence of 
life in Archaean times has yet been discovered in the Dharwar 
rocks ; but it is justified on grounds of general degree of meta- 
morphism, folding, and relationship to other Archaean forma- 
tions. It is probable that no one area shows the complete 
General contempora 
neity of Dhiraceu. for- 
in 
deposition giving rise to considerable unconformities within 
t. ars. 
Secondly, as regards the bib of the rocks comprising the 
ar formations, I prefer with 
Po, gun sre rel aoe get let Middlemiss to await the production of 
evidence by the Mysore Geological 
Sis cca a oe their eaten conclusions as 
the origin of the Dharwar schists. But I am probably 
